Roger Federer lost to Tommy Robredo 7-6, 6-3, 6-4 in a stunning round of 16 match at the U.S. Open.

Playing on Louis Armstrong Stadium — only the tournament's second-biggest court — for the first time since 2006, Federer made dozens of unforced errors and blew a series of critical break point chances.

If he had won, Federer would have likely played Rafael Nadal in what would have been a mouth-watering quarterfinal match.

They have still, amazingly, never met at the U.S. Open.

Federer is past his prime and has struggled with a back injury all summer. But it was still startling to see one of the best players ever lose so convincingly.

He was simply dismantled tonight. Federer had 43 unforced errors, was 2-for-16 on break point chances, and was out of sorts all match long.

On the other hand, at age 31, this might be the highlight of Robredo's career.